Rural Emergency Medicine

Seizures are defined as excessive, abnormal cortical neuronal activity resulting in a variety of physical symptoms. Seizures / convulsions persisting beyond 5 minutes can be thought to be Status Epilepticus, and increase the risk of complications (including death) to the individual. Status Epilepticus has a higher mortality in Adults than it does in Children.

Treatment is aimed at terminating the seizure as soon as possible, identifying cause, maintenance of ABCs, and avoiding/minimizing complications where possible.

This is part of the Rural Emergency Module series (designed in particular for ACRRM Trainees).

Initial Assessment and Management

Recognition
  • Recognise, send for help, gather resources and appropriate equipment. 
  • Protect patient and self from further danger.
  • Move to resuscitation bay, when safe to do so.
  • Monitoring.
Generalized status epilepticus is currently defined as either:
  • Ongoing convulsive seizure > 5 minutes
  • Recurrent seizures without normalization of consciousness between seizures.


Airway:
  • Check airway. 
  • Manage airway with recovery position, airway adjuncts and intubation if required.
  • Give oxygen as indicated.
  • Suction for secretions. Clear vomitus.
  • C-Spine precautions (only if trauma suspected)
Breathing:
  • If breathing is inadequate, assist with BVM + high flow oxygen (prone to hypercapnia)
  • Place on at least some Nasal Prongs / NRB mask initially.
  • Avoid hypoxia.
Circulation:
  • Early access – PIVC or IO
  • IV fluid line (primed and ready to go)
Disability:
  • Level of consciousness – GCS, AVPU
  • Check BSL
  • Focal neurology
  • Pupil response
  • Meningism
  • Lateral tongue biting
Exposure:
  • Check temp, maintain Normothermia.
  • Reminder to check bedside BSL + VBG if able
  • Correct electrolyte disturbances


 Terminate Seizure
  • First Line: Benzodiazepines – Bolus dose, route dependent on ease and drug choice
  • Second Line: usually require intubation + mechanical ventilation.
    • IV Phenytoin: 15-20 mg/kg IV over 30 minutes or longer
    • IV Sodium Valproate: 40 mg/kg IV over 10 minutes
    • IV Midazolam infusion: 0.1 – 1.0 mg/kg/hr, titrate to effect 
    • Can consider IV Levetiracetam (off-label use for Status Epilepticus)
  • Third Line: intubation + mechanical ventilation + cEEG monitoring if available
    • IV Barbiturates: Phenobarbitone, Thiopentone
    • IV Propofol: 2-3mg/kg IV then < 4mg/kg/hr
    • IV Clonzepam 
  • Fourth line: intubation + mechanical ventilation + cEEG monitoring if available
    • IV Ketamine
    • Volatile Anaesthetic Agent

 Identify and treat underlying cause

Differential diagnosis of conditions that mimic seizures
  • Eclampsia
  • Nonepileptic seizures/ pseudoseizures
  • Syncope
  • Acute dystonic reactions
  • Rigors
  • Cardiac disorders (e.g. Dysrhythmias, Long QT syndrome, HOCM)


History
Signs/symptoms
  • Seizure activity
  • Time of onset and offset (i.e. duration)
  • Warning signs
  • Parts of body involved in motor activity, and sequence of involvement
  • New vs recurrent
  • Fever
  • Pregnant / Post-partum (think Eclampsia)
  • Other clues regarding precipitants or factors which would lower seizure threshold
Allergies
Meds 
  • Antiepileptics (? Compliance)
  • Antipsychotics, antidepressants, isoniazid
  • Recreational drugs, drug withdrawal
  • Insulin therapy
PMHx:
  • Pre-existing hx of epilepsy, family hx, Renal Failure, Endocrinopathies
  • Alcohol +/- drug abuse
Last oral intake
  • Poison ingestion
Events
  • As per above, looking for factors that may guide the cause for the seizure.

Red Flags
  • Persistent GCS < 14
  • Hx of Status Epilepticus
  • Hx of Malignancy
  • Alcohol Withdrawal
  • Pregnancy / Post-partum

Investigations
  • VBG – Glucose + Basic Electrolytes + Lactate
  • Urine Dipstick (and don't forget BhCG in females) + Formal M/C/S if indicated
  • FBC + Chem20 (U&E + LFTs + Ck + CMP)
  • Anticonvulsant Levels
  • 12-lead ECG (if considering toxins)
In Rural Hospitals (with Theatre capabilities), Bispectral index (BIS) monitoring may also provide some information to guide clinical management (when formal EEG monitoring is not available).

Also consider in select circumstances and as availability dictates;
  • CT Head
  • Lumbar Puncture (concern re: CNS infection
  • Blood/Urine Cultures
  • Toxicology Screens
  • EEG


Management
This is one management approach to Afebrile Seizures given medication availability in Rural Hospitals. Please check your local protocols regarding specific medications. Maintenance of the ABCs is important, however it is useful to keep in mind that prioritizing the abortion of the seizure will often also optimise ABCs.


Anti-Epileptic Drugs

For individuals already on an Anti-Epileptic Drug/s (AED) often reloading their regular AED is an appropriate strategy for ongoing prophylaxis.

Supportive Cares

  • Fluid therapy and feeding: targeted fluid therapy to correct; hypoglycaemia, other metabolic and electrolyte derangements (e.g. hyper/hyponatraemia), hypovolaemia, rhabdomyolysis
  • Anti-emetics: coughing and straining increases ICP, reduce chance of vomitus and potential airway hazards
  • Antibiotics / Antivirals: in suspected bacterial / viral infections.
  • Sedation and analgesia: Sedation to aid in terminating seizure.
  • Thromboprophylaxis: routine indications
  • Head: lateral / recovery position. head up position (30 degrees) in head injury or to reduce ICP
  • Ulcer prophylaxis: typically not required.
  • Glucose control: aim for normoglycaemia
  • Skin/eye care
  • Indwelling catheter: to decrease intra-abdominal pressure and monitor urine output
  • Nasogastric tube: orogastric is the preferred option in head trauma patients. Should be performed after intubation.
  • Bowel cares
  • Environment: Maintain Normothermia (Temp 36-37; give antipyretics if Temp >38C) to prevent a rise in cerebral metabolic rate.

Rapid Sequence Termination (RST) of status epilepticus

Dr Josh Farkas from Pulmcrit.org has developed his own algorithmic approach to treatment of Status Epilepticus with some further discussion around the role of intubation. See the Resuscitationist’s guide to status epilepticus on Emcrit.org for more details.



Febrile Seizures 

Febrile Seizures or convulsions typically occur between the ages of 6 months and 6 years. Most of these seizures resolve spontaneously and do not require anti-convulsant agents.

For more information on Febrile Seizures see the following Royal Children's Hospital Guideline.

Post-Seizure

Some key considerations post-seizure for the Rural Health Practitioner include;
  • Disposition; transfer to another facility / ward / HDU
  • Specialist input: Neurologist +/- other critical care specialties as indicated
  • Driving: Patients should be advised that they are not to drive for at least 6 months and after specialist clearance. Check your local regulations regarding time-frames and reporting.

References / Further Resources


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